Palladium-catalyzed cross-coupling reactions, e.g., the Suzuki coupling, the Stille coupling, the Heck coupling, the Sonogashira coupling, the arylation of aryl halides with ketones and esters, and the amination of aryl halides with amines, etc., are among the most powerful tools for the synthesis of biologically active compounds. The work described in this proposal is aimed at the development of more powerful catalysts for these reactions, primarily focusing on complexes that employ rigid and sterically regular monodented ligand containing polymers as ligands. We intend to develop extremely highly active palladium catalysts for coupling organic chlorides at room temperature and for carbon-carbon and carbon-heteroatom bonding formations that are difficult or impossible to be realized by using existing catalyst systems. Although our primary objective is to provide highly active palladium catalysts that will be widely applied by synthetic chemists both in pharmaceutical/chemical development and basic research, we will also carry out mechanistic studies directed at furnishing insights of the origin of the unusual catalytic activity of (monodented ligand-containing polymer)/Pd complexes in the coupling processes.